title: The cortical response to the oral perception of fat emulsions and the effect of taster status.
abstract: The rewarding attributes of foods containing fat are associated with the increase in fat consumption, but little is known of how the complex physical and chemical properties of orally ingested fats are represented and decoded in the brain nor how this impacts feeding behavior within the population. Here, functional MRI (fMRI) is used to assess the brain response to isoviscous, isosweet fat emulsions of increasing fat concentration and to investigate the correlation of behavioral and neuroimaging responses with taster status (TS). Cortical areas activated in response to fat, and those areas positively correlated with fat concentration, were identified. Significant responses that positively correlated with increasing fat concentration were found in the anterior insula, frontal operculum and secondary somatosensory cortex (SII), anterior cingulate cortex, and amygdala. Assessing the effect of TS revealed a strong correlation with self-reported preference of the samples and with cortical response in somatosensory areas [primary somatosensory cortex (SI), SII, and midinsula] and the primary taste area (anterior insula) and a trend in reward areas (amygdala and orbitofrontal cortex). This finding of a strong correlation with TS in somatosensory areas supports the theory of increased mechanosensory trigeminal innervation in high 6-n-propyl-2-thiouracil (PROP) tasters and has been linked to a higher risk of obesity. The interindividual differences in blood oxygenation level-dependent (BOLD) amplitude with TS indicates that segmenting populations by TS will reduce the heterogeneity of BOLD responses, improving signal detection power.
authors.affiliation: Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: Sally
authors.initials: S
authors.lastname: Eldeghaidy
authors.forename: Luca
authors.initials: L
authors.lastname: Marciani
authors.forename: Francis
authors.initials: F
authors.lastname: McGlone
authors.forename: Tracey
authors.initials: T
authors.lastname: Hollowood
authors.forename: Joanne
authors.initials: J
authors.lastname: Hort
authors.forename: Kay
authors.initials: K
authors.lastname: Head
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Taylor
authors.forename: Johanneke
authors.initials: J
authors.lastname: Busch
authors.forename: Robin C
authors.initials: RC
authors.lastname: Spiller
authors.forename: Penny A
authors.initials: PA
authors.lastname: Gowland
authors.forename: Susan T
authors.initials: ST
authors.lastname: Francis
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D004041:Dietary Fats / Q000008:administration & dosage*; D045703:Emulsifying Agents / Q000008:administration & dosage*; D004655:Emulsions; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009055:Mouth / Q000502:physiology*; D013649:Taste / Q000502:physiology*; D055815:Young Adult
chemical_list: D004041:Dietary Fats; D045703:Emulsifying Agents; D004655:Emulsions